Clinical outcomes for T1-2N0-1 oral tongue cancer patients underwent surgery with and without postoperative radiotherapy

Table 2 Univariate analysis of five-year disease-free survival (DFS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS) rate, and overall survival (OS) rate

	5-year DFS		5-year LRFS		5-year RRFS		5-year DMFS		5-year OS
	(%)	p value	(%)	p value	(%)	p value	(%)	p value	(%)	p value
Age (year)		0.233		0.239		0.712		0.312		0.789
< 55	84		97		84		89		84
≥ 55	77		87		78		93		77
Performance		0.718		0.162		0.44		0.692		0.421
ECOG 0	87		100		87		87		87
ECOG 1	77		88		78		94		78
T classification		0.331		0.575		0.101		0.856		0.186
T1	84		91		85		96		86
T2	74		94		73		83		71
N classification		0.725		0.963		0.52		0.856		0.186
N0	81		92		82		91		83
N1	79		93		79		92		67
Stage		0.568		0.685		0.218		0.228		0.151
I	85		90		86		96		87
II	72		96		72		82		73
III	79		93		79		92		67
Grade		0.005		0.015		0.013		0.024		0.001
Well	88		95		89		96		91
Moderate-poor	69		86		69		84		65
Invasion depth (cm)		0.018		0.166		0.008		0.201		0.023
≤ 0.5	92		98		92		96		92
> 0.5	66		83		66		87		66
Resection margin		0.186		0.624		0.081		0.292		0.360
Negative	84		92		86		94		84
Close (< 0.5 cm) or positive	65		89		62		86		67
Lymphovascular invasion		0.358		0.686		0.292		0.043		0.586
Yes	67		100		67		67		50
No	81		91		82		93		82
Perineural invasion		0.662		0.135		0.598		0.602		0.283
Yes	67		67		50		100		67
No	81		93		82		91		81
Radiotherapy		0.475		0.161		0.775		0.548		0.647
Yes	86		100		86		86		86
No	79		90		80		93		80
Operation of primary site		0.284		0.608		0.775		0.548		0.647
Simple excision	74		83		74		100		81
Hemiglossectomy	78		82		80		89		81
Wide excision	100		100		100		100		100
Neck dissection		0.534		0.556		0.518		0.898		0.882
Yes	82		93		83		92		81
No	76		88		75		90		80

ISSN: 1748-717X